MLA

Van Vechten, Carl, 1880-1964. Rainer, Luise. Box 371, folder 5300. 1937 September 2. https://collections.library.yale.edu/catalog/10001377.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 371, folder 5300"])(1937 September 2)[Rainer, Luise]. https://collections.library.yale.edu/catalog/10001377.